KEEPING AN EYE ON CONTACT LENSES

United Press InternationalCHICAGO TRIBUNE

The contact lens business is booming, and a scientist-businessman is convinced that the gas permeable lens, a hybrid combining the comfort of soft lenses with the visual acuity provided by hard lenses, is the wave of the future.

Perry Rosenthal, an opthomologist and assistant clinical professor at Harvard University, is chairman of Polymer Technology Corp., a firm that developed the gas permeable plastic material.

Two years ago Rosenthal sold Polymer, which he founded in 1972, to Bausch & Lomb, the largest contact lens company in the world, for $22 million in cash, and stayed on as chairman of the independent subsidiary.

In two years, Polymer has become the second fastest growing division of Bausch & Lomb, and sales have far surpassed expectations.

''We`re having a significant impact on the earnings and share price,'' he said.

Part of the reason is the continuing popularity of all contact lenses. The market for soft and hard lenses is growing at a rate of 25 percent a year. The market for rigid, gas permeable lenses, such as those developed by Polymer, is growing even faster, about 50 percent a year, Rosenthal said.

The Polymer lens, sold under the trade name The Boston Lens, has the largest market share of rigid gas permeable lenses today, he said.

Polymer also develops and sells cleaning and wetting solutions for use with all gas permeable lenses. That is a major part of the contact lens business, since lens wearers spend more on cleaners and solutions--about $200 million annually--than they spend on lenses.

Polymer does not manufacture the lenses, but sells plastic lens material to 75 laboratories around the United States, which in turn manufacture the lenses to doctors` specifications.

Because the gas permeable lens is rigid, said Rosenthal, it corrects astigmatism, an irregularity of the curvature of the cornea, the delicate transparent tissue that the contact lens sits on. An estimated 40 percent of the population has astigmatism.

Rigid gas permeable lenses also have advantages over traditional hard contact lenses, he said, since they allow oxygen to pass from the air to the cornea--the only surface tissue of the body that requires a constant supply of oxygen directly from the air, rather than from the blood.

The Boston Lens is made of silicone, which contains oxygen atoms, allowing most gases to pass through the material even though it is solid.

The Polymer lenses, which Rosenthal began developing at his laboratory in Wilmington, Mass., in 1972, are about twice as expensive as soft lenses, costing between $200 and $400. But the rigid lens is more durable, and does not need to be replaced as often, he said.